急性阿片耐受大鼠脊髓NMDA受体NR2A及NR2B亚基表达的改变  

Expression of the NMDA receptor NR2A and NR2B subunits in the spinal cord of acute opioid tolerance rats

作　　者：杜金[1] 黄宇光[2] 

机构地区：[1]扬州大学苏北人民医院麻醉科 [2]北京协和医院麻醉科,北京100730

出　　处：《中国临床药理学与治疗学》2010年第1期59-65,共7页Chinese Journal of Clinical Pharmacology and Therapeutics

摘　　要：目的：了解大鼠短期多次应用芬太尼能否发生急性阿片耐受以及急性阿片耐受大鼠脊髓NMDA受体NR2A和NR2B亚基表达的改变。方法：24只体重为200-220g的雄性SD大鼠随机分为3组（n=8）：对照组（C）,生理盐水组（S）及芬太尼组（F）。F组大鼠给予皮下注射芬太尼30μg/kg,共4次,每两次注射之间间隔15min,S组大鼠以生理盐水代替芬太尼,C组大鼠未给药。给药前及给药结束后每30min以Von-Frey仪测定各组大鼠的机械刺激缩足阈值（paw withdrawal threshold,PWT）。当F组大鼠的PWT恢复到给药前基础水平时,各组大鼠均给予腹腔注射吗啡5mg/kg。随后仍每30min测定各组大鼠的PWT,直至F组大鼠的PWT再次回到基础水平。对各组大鼠不同时间点的PWT进行组内和组间比较。另24只体重为2000-220g的雄性SD大鼠分组及给药方法同前（分为C^＊、S^＊及F^＊组）,当F＊组大鼠的PWT首次恢复到基础值时,不给予吗啡,处死各组大鼠,取脊髓,以Western blotting方法测定NMDA受体NR2A及NR2B亚基的蛋白表达水平。结果：连续4次皮下注射芬太尼（F组）后大鼠首先表现为PWT较基础值显著升高,随后PWT降低到基础值以下,然后逐渐恢复至基础值水平,此时皮下注射吗啡后,吗啡的镇痛效果显著低于其他两组大鼠（S组,C组）。F^＊组大鼠脊髓的NR2B亚基表达水平显著高于C^＊组及S^＊组,各组大鼠脊髓的NR2A亚基表达水平的差异无统计学意义。结论：短期应用芬太尼可导致大鼠发生急性阿片耐受。急性阿片耐受大鼠的脊髓NMDA受体NR2B亚基表达水平显著升高,NR2A亚基表达水平无明显变化。AIM： To observe the acute opioid tolerance repeated application of fentanyl in short term and examine the effects of acute Fentanyl administration on protein expression of two major NMDA receptors subunits （NR2B and NR2A） in the spinal cord of rats. METHODS： 24 male Sprague-Dawley rats, weighing 200- 220 g, were randomly divided into three groups with 8 rats each. Control, Saline and Fentanyl group. Fentanyl was injected subcutaneously four times at 15 min intervals （30 μg/kg per injection） in Fentanyl group. Rats in Saline group received saline injections instead of Fentanyl. And no injections were given to the rats of Control group. The paw withdrawal threshold （PWT） were measured every 30 min with a VonFrey hair test. When the PWT of Fentanyl group returned to the baseline which had been measured before injection, an injection of morphine （5 mg/kg） was performed to every rat of these 3 groups. Subsequent changes of PWT were still measured every 30 min until the PWT of Fentanyl group returned to the baseline again. The PWT at each time point were compared with the baseline and the corresponding one of the other two groups. Another 24 male Sprague-Dawley rats, were randomly divided into three groups with 8 rats each： Control^＊ , Saline^＊ and Fentanyl^＊ group. Fentanyl was administrated as above except no morphine administrated. When the PWT of Fentanyl^＊ group returned to the baseline, all of the rats were killed. The spinal cord was sampled and the protein levels of NR2B and NR2A subunits were tested with the Western blotting method. RESULTS： Four fentanyl boluses （in group F） elicited an increase followed by an immediate decrease of the PWT and reduction of the analgesic effect of a subsequent morphine administration compared with the other two groups. According to the results of Western blotting, in spinal cord, the protein level of NR2B subunit of Fentanyl ^＊ group were higher than that of the Control^＊ and Saline^＊ group, but there was no difference of the prote

关 键 词：急性阿片耐受 芬太尼 吗啡 NMDA受体NR2A亚基 NMDA受体NR2B亚基 

分 类 号：R965.2[医药卫生—药理学]